DatabaseImpl is the XML:DB driver implementation for Xindice. It is the entry
point into the Xindice server but is not intended for direct use by users.
Users access it indirectly through the XML:DB DatabaseManager implementation.

getCollection

Creates a Collection instance using the URI to locate the collection in
the Xindice instance. Applications should not call this method directly.
Instead they should call DatabaseManager.getCollection(String, String, String).

Database host is optional.
This usually looks something like this:
xindice:///db/root/ocs or
xindice://some.host.com:8309/db/root/ocs

When you pass the URI to DatabaseManager.getCollection(uri) you must
prepend an xmldb: to the beginning to make it a valid XML:DB URI.
So to normal users of the API URIs will look like this:
xmldb:xindice:///db/root/ocs. DatabaseManager will strip the
xmldb: before handing the URI to this getCollection implementation.